The avatar is like a Rorschach inkblot, or the Draw-a-House/Person/Tree Test, or any work of art. It is selected from personal imagination. Consciously or unconsciously, people condense a multitude of meaning into it. They project their personality into it -who they are, who they wish to be, what they fear, what moves them.
Choose one of your icons, and post it up in your journal. Then ask people to comment with the first thing that comes to mind when they see that icon -- whether it's associated with the image, the text, or with the identity/mood they project on you when you're using it, whatever. Free association. See if anything fits.
This is my default icon: